notebook - Southwest Florida Water Management District

E. Drainage Information
1. Provide pre-development and post-development drainage calculations, signed and sealed by an
appropriate registered professional, as follows:
a. Runoff characteristics, including area, runoff curve number or runoff coefficient, and time of
concentration for each drainage basin;
b. Seasonal high water table elevations including aerial extent and magnitude of any proposed
water table drawdown;
c. Normal, wet season and design storm elevations of receiving waters;
d. Design storms used including rainfall depth, duration, frequency and distribution;
e. Runoff hydrograph(s) for each drainage basin, for all required design storm event(s);
f. Stage-storage computations for any area such as a reservoir, closed basin, detention area, or
channel used in storage routing;
g. Stage-discharge computations for any storage areas at a selected control point, such as
control structure or natural restriction;
h. Flood routings through on-site conveyance and storage areas;
i. Water surface profiles in the primary drainage system for each required design storm
event(s);
j. Runoff peak rates and volumes discharged from the system for each required design storm
event(s);
k. Tail water history and justification (time and elevation);
l. Pump specifications and operating curves for range of possible operating conditions (if used
in system).
2. Provide the results of any percolation tests, where appropriate, and soil borings that are
representative of the actual site conditions.
3. Provide the acreage and percentage of the total project, of the following:
a. impervious and semi-impervious surfaces, excluding wetlands;
b. pervious surfaces (green areas not including wetlands);
c. lakes, canals, retention areas, other open water areas;
d. wetlands.
4. Provide an engineering analysis of floodplain storage and conveyance (if applicable), including:
a. Hydraulic calculations for all proposed traversing works;
b. Backwater water surface profiles showing upstream impact of traversing works;
c. Location and volume of encroachment within regulated floodplain(s);
d. Plan for compensating floodplain storage, if necessary, and calculations required for
determining minimum building and road flood elevations.
5. Provide an analysis of the water quality treatment system including:
a. A description of the proposed stormwater treatment methodology that addresses the type of
treatment, pollution abatement volumes and recovery analysis;
b. Construction plans and calculations that address stage-storage and design elevations, which
demonstrate compliance with the appropriate water quality treatment criteria.
6. Provide a description of the engineering methodology, assumptions and references for the
parameters listed above, and a copy of all such computations, engineering plans and specifications
used to analyze the system. If a computer program is used for the analysis, provide the name of
the program, a description of the program, input and output data, two diskette copies, if available,
and justification for model selection.
FORM 547.27/ERP (084/1109) Section E - Page 4 of 5 RULE 40D-4.101(1)(b), F.A.C.
36